Abstract:

CuCNn (n=1,2,3) catalysts with different Cu loading amounts were prepared by thermal condensation using urea and Cu(NO₃)₂·3H₂O as precursors, The structures and morphology of the catalysts were characterized by XRD, FTIR, XPS, BET, SEM and TEM. The catalytic performance of Cu/CNn with different Cu loading amounts was compared in the atom transfer radical addition (ATRA) reaction of CCl₄ with acrylonitrile (AN) to synthesize 2,4,4,4-tetrachlorobutanitrile (TBN). The results showed that the Cu/CN1 exhibited excellent catalytic performance. Using acetonitrile (MeCN) as a solvent, n(Cu/CN1)∶n(AN)=1∶1000, 120℃, for 12h, the selectivity and yield of TBN can reach 96.5% and 83.3%, respectively. As a heterogeneous catalyst, Cu/CN can be reused only after filtration treatment, and its catalytic activity can still be stably maintained after 7 times of use. Based on the relevant experimental results, the oxidation-reduction cycle ATRA reaction mechanism of CCl₄ and AN catalyzed by Cu/CN was proposed. The results of experiments revealed the synergistic mechanism of Cu and g-C₃N₄, providing a new idea for the development of efficient catalytic systems for CCl₄ deep processing.

Key words: 2,4,4,4-tetrachloronitrile, g-C₃N₄, Cu/CN catalyst, atom transfer radical addition (ATRA)

摘要：

以尿素和Cu(NO₃)₂·3H₂O为前体，采用热缩合法制备了不同Cu负载量的氮化碳（g-C₃N₄）基催化剂Cu/CNn（n=1、2、3），采用X射线衍射仪、傅里叶变换红外光谱、X射线光电子能谱、比表面积测试、扫描电子显微镜及透射电子显微镜对其结构和形貌进行了表征，比较了不同Cu负载量的Cu/CNn催化CCl₄与丙烯腈（AN）的原子转移自由基加成（ATRA）反应合成 2, 4, 4, 4-四氯丁腈（TBN）的催化性能。结果表明，Cu/CN1呈现优异的催化性能，以乙腈（MeCN）为溶剂，n(Cu/CN1)∶n(AN)=1∶1000，120℃反应12h，TBN 的选择性可达96.5%，产率可达83.3%，Cu/CN作为多相催化剂，经过滤处理便可重复利用，使用7次其催化活性仍能稳定保持。基于相关的实验结果，提出了Cu/CN催化 CCl₄ 和AN 的 ATRA反应的氧化-还原循环机理。实验结果揭示了Cu与g-C₃N₄载体的协同作用机制, 为CCl₄深加工开发高效的催化体系提供了新的思路。

关键词: 2,4,4,4-四氯丁腈, 氮化碳, Cu/CN催化剂, 原子转移自由基加成